Chapter 6.2, Problem 14LC

(a)

Interpretation Introduction

Interpretation:Barium to be identified as an alkali metal, alkaline earth metal, or halogen.

Concept introduction:

The periodic table is a columnar structure that organizes different elements into groups based on how they behave. The elements in the periodic table of today are ordered according to the periodic law. The elements are organized in the modern periodic table in increasing order of their atomic number.

Answer to Problem 14LC

Alkaline earth metal

Explanation of Solution

The atomic number of Barium is 56 and itsouter shell electronic configuration is,$\left[\text{Xe}\right]6s^2$

The last electron in the s-subshell, so it is ans-block element. The outer shell or highest occupied energy level contains2electrons; thus, it belongs to group 2A. The group 2A elements are called alkaline earth metals.

Thus, Barium is an alkaline earth metal.

(b)

Interpretation Introduction

Interpretation:Lithium to be identified as an alkali metal, alkaline earth metal, or halogen.

Concept introduction:

The periodic table is a columnar structure that organizes different elements into groups based on how they behave. The elements in the periodic table of today are ordered according to the periodic law. The elements are organized in the modern periodic table in increasing order of their atomic number.

Answer to Problem 14LC

Alkali metal

Explanation of Solution

The atomic number of Lithium is 3 and itsouter shell electronic configuration is,$1s^{2}2s^1$

The last electron in the s-subshell, so it is ans-block element. The outer shell or highest occupied energy level contains 1 electron; thus, it belongs to group 1A. The group 1A elements are called alkali metal

Thus, Lithium is an alkali metal.

(c)

Interpretation Introduction

Interpretation:Chlorine to be identified as an alkali metal, alkaline earth metal, or halogen.

Concept introduction:

The periodic table is a columnar structure that organizes different elements into groups based on how they behave. The elements in the periodic table of today are ordered according to the periodic law. The elements are organized in the modern periodic table in increasing order of their atomic number.

Answer to Problem 14LC

Halogen

Explanation of Solution

The atomic number of Chlorine is 17 and itsouter shell electronic configuration is,$\left[\text{Ne}\right]3s^{2}2p^5$

The last electron in the p-subshell, so it is a p-block element. The outer shell or highest occupied energy level contains 7electrons; thus, it belongs to group 7A. The group 7A elements are called halogens

Thus, chlorine is a halogen.

(d)

Interpretation Introduction

Interpretation:Berylliumis to be identified as an alkali metal, alkaline earth metal, or halogen.

Concept introduction:

The periodic table is a columnar structure that organizes different elements into groups based on how they behave. The elements in the periodic table of today are ordered according to the periodic law. The elements are organized in the modern periodic table in increasing order of their atomic number.

Answer to Problem 14LC

Alkaline earth metal

Explanation of Solution

The atomic number of Beryllium is 4 and itsouter shell electronic configuration is,$\left[\text{He}\right]2s^2$

The last electron is in the s-subshell, so it is ans-block element. The outer shell or highest occupied energy level contains 2electrons; thus, it belongs to group 2A. The group 2A elements are called alkaline earth metals

Thus, beryllium is an alkaline earth metal.